Uranium occurrences in Malakand granite and granitic gneisses, Malakand Agency, N.W. Pakistan

Abstract

Uranium prospection in granitic rocks of Indian plate has yielded numerous radiometric and geochemical uranium anomalies. Detailed investigation on some of radioactive anomalies in alkaline granite of alkaline igneous province revealed that they are mostly thorium dominant. In most of the rocks, uranium is locked in refractory phases such as monazite and thorite, precluding any significant late stage uraninite crystallization. The detailed foot radiometric survey in Malakand granite gneiss, however, resulted in locating anomalous radioactivity of uranium dominant character with uraninite as a radioactive mineral. A highly radioactive zone at Baru near Kot village was subjected to details surface and subsurface exploration through diamond core drilling. The collected data revealed that high chemical uranium values are due to uraninite, which occurs as inclusion in biotite along joint planes parallel to regional foliation. The joint planes are generally associated with pegmatites,

Secondary mineralization in the form of torbemite, metatorbernite and uranophane were also noted along some fracture of water seepage. The occurrence of uraninite seems to be related with pnematolytic Stage with some limited metasomatic alteration. This paper presents the type, nature and intensity of uranium mineralization in Malakand granite in general and Baru prospect in particular. The paper also assesses the potential of Baru prospect for a Viable uranium deposit.